(1) Field of the Invention
The invention relates to a device and a method for shrinking packages by having a liquid and/or vaporous heating device on a packaging machine and using a liquid and/or vaporous heating medium with a packaging machine. More particularly, the invention relates to a packaging machine having a recirculation apparatus for recirculating a heating medium and a process for recirculating a heating medium for a packaging machine.
(2) Description of Related Art Including Information Disclosed under 37 C.F.R. 1.97 and 1.98
In order to package items in packages with largely form closure, it is customary to package, for example weld in, the items in shrinkable packaging materials, for example shrinkable plastic films. The packaging is then made to shrink by heating so that the packaging contracts around the packaged items. To do this, in commercially available packaging machines so-called shrinking tunnels or shrinking tanks are used in which water is heated. The packages with the packaging which is to be shrunk on are wetted here with hot water. The continuous generation of vapor results in a large amount of energy being required in such devices.